The present invention relates to control means for internal combustion engine and pertains particularly to a governor control linkage for internal combustion engines equipped with variable speed governor.
Many industrial vehicles are powered by engines of the internal combustion piston type. Such internal combustion engines employ mixing and metering devices for metering the fuel to the combustion chambers. The flow of fuel to the combustion chamber frequently determines the speed of the engine. Such metering devices may take the form of injectors or carburetors.
In order to maintain a substantially constant speed of the engine for varying loads, a governor is normally employed which is responsive to engine speed for altering the setting of the fuel flow or mixture to the combustion chambers. Variable speed governors are normally employed in vehicles or engines for vehicles which may undergo frequent adjustment by the operator in the speed of the engine.
The governor setting which determines the engine speed is set by an operator control element movable by the operator to select settings to establish a predetermined setting for the governor. The governor may employ numerous devices such as centrifugal weights or the like wherein the position of the weight is determined by a force acting thereon in addition to the speed of the engine. With such governors the force required for establishing a selected setting increases with increasing engine speed.
Many vehicles such as industrial lift trucks and the like employ implements which require precise and easily controllable manipulation by the operator. It is desirable for this reason that the controls of the vehicle be substantially uniform in feel throughout its control range. This is especially so of the throttle or speed control of the vehicle, especially when precise control of the engine speed is frequently required.
It is therefore desirable that the uneven and excessive force required on the operator control element be eliminated, if possible. Accordingly, the present invention is directed to this end.
While the applicants are not aware of any prior art recognition of this problem or any proposals for solving the problem, the following prior art is of interest in regards to governor control in general: U.S. Pat. Nos. 2,716,397, issued Aug. 30, 1955 to Heinish; U.S. Pat. No. 3,130,599, issued Apr. 28, 1964 to Haas; and U.S. Pat. No. 3,157,167, issued Nov. 17, 1964 to Walker, et al.